Locking means for a stand



Aug. 26, 1958 R. E. PETRICK ET AL LOCKING MEANS FOR A STAND OriginalFiled July 21, 1950 United States Patent LOCKING MEANS FOR A STANDRussell E. Petrick and Edward J. Petrick, Park Ridge, Ill., assignors toBretford Manufacturing, Inc., Franklin Park, 111., a corporation ofIllinois Original application July 21, 1950, Serial No..175,164,

now Patent No. 2,703,690, dated March 8, 1955. Divided and thisapplication June 22, 1953, Serial No. 363,124

3 Claims. (Cl. 248--161) This invention relates to supporting stands forlamps and the like, and more particularly to a means for locking atelescoping stand in varying degrees of extended position. This is adivisional application of our copending application, Serial No. 175,164,entitled Lamp Stand, and filed July 21, 1950, now Patent 2,703,690.

The primary object of this invention is to provide a simple andetfective means for gripping and retaining a telescoping stand in anydesired position of extension.

Another object is to provide a locking means for a stand having a springassociated therewith for normally urging the locking means into grippingengagement with an extensible member in the stand.

A further object is to provide a spring for a locking means whichassists in centering a telescoping member in the stand and releasablysecures a cap for the locking means in its bayonet slot.

Another object is to provide a friction means for a telescoping standwhich will restrain a telescoping member from dropping downwardly whenthe locking means is released.

A further object is to provide a locking means for a stand which can bequickly and easily assembled or dismantled.

Still another object is to provide a locking means which can be cheaplyand easily manufactured.

The invention is illustrated in the preferred embodiment in theaccompanying drawings, in which:

Fig. 1 is a perspective view of the supporting stand shown in use with alamp;

Fig. 2 is a sectional view through the locking means of the supportingstand;

Fig. 3 is a side view of the cap shown in Fig. 2; and

Fig. 4 is a sectional view of Fig. 2 taken along line 4-4 as indicated.

In the embodiment illustrated, a supporting stand generally designatedhas a tripod base 11 of conventional construction and an extensible rod12 capable of telescoping within the tubular supporting standard ormember 13. The locking means 14 is normally in gripping engagement withthe extensible rod to hold the rod in varying degrees of extendedposition. As shown in Fig. 1, the stand is serving as a support for alamp 15 which engages the extensible rod through a connector 16 and thelamp rod 17. The lamp is for illustrative purposes only, and forms nopart of the present invention. It is obvious that the stand couldlikewise be employed with music racks, movie screens or the like.

As best shown in Fig. 2, the extensible rod is telescoped within thetubular supporting member, there being secured adjacent the end of therod a piston-like washer 18 which is preferably made of some resilientmaterial such as rubber or plastic. The washer engages the innersurfaces of the tubular supporting member and centers the lower portionof the rod in this member. The washer may be notched (not shown) to fitthe inturned crimp 31. When this is done, the crimp 31 serves as a guideto prevent rotationof the extensible rod about its longitudinal axis.

2,849,204 Patented Aug. 26, 1958 The ear-like projections 19 on the rodprevent it from being removed from the tubular supporting member whilethe stand is in operation. I

As best shown in Fig. 3, the upper end of the tubular supporting memberis preferably covered by a cap 20 which has a centrally disposed opening21 through its top to slidingly receive the extensible rod. The cap isprovided with a lug 23 which is adapted to fit into a bayonet slot 24provided in the end of the tubular supporting member. The bayonet slotextends laterally of the supporting member as at 24m and has an upwardlyextending seat 24b into which the lug 23 may be fitted. A longitudinalslot 240 is provided so that the lug may be moved downwardly toward itslocking position in the bayonet slot. Thus when the cap is in properposition and turned, it is firmly held in attached position upon the endof the tubular supporting member by an upwardly bearing compressionspring 32, to be discussed later.

As best seen in Fig. 2, locking means is herein positioned near the topof the tubular supporting member. An L-shaped lever 25, sometimesreferred to as a nipping lever, having a clamping member 26 and a fingerarm 27 is fulcrumed in the slot 28 in the tubular supporting member. Theclamping member 26 has a centrally disposed opening 29 therein throughwhich the extensible rod extends. When the clamping member is normal tothe rod, the rod is freely received within the opening. However, whenthe arm is inclined from the normal into gripping or locking position,the edges about the opening in the clamping member 26 impinge upon theextensible rod and hold it fast until the member is again returned to asubstantially normal position. The finger arm 27 is preferably formedintegrally with the clamping member 26, and when depressed, it pivotsthe member 26 about its fulcrum point. In the embodiment illustrated,the clamping member 26 has a notch 30 to accommodate the inturned crimp31 of the tubular supporting member.

The compression spring 32 is positioned within the tubular supportingmember and below the cap so that it embraces the extensible rod. Thisspring performs at least three distinct functions. First, it urges theclamping member 26 into gripping engagement with the extensible rod.Secondly, it yieldingly bears against the underside of the cap toreleasably secure the cap in position in the bayonet slot. And, thirdly,it holds a friction sleeve 33, usually composed of a piece of felt,around the extensible rod to prevent the rod from rapidly falling whenthe locking means is released.

In operation, the extensible rod is normally held in gripping engagementby the clamping member 26 of the locking means. To extend the stand, itis merely necessary to grasp the extension rod and pull it outwardlyagainst the yielding pressure of the compression spring. This outwardpull positions the member 26 substantially normal to the extension rodand allows the rod to move easily therein. extension rod is limited bythe ear-like projections 19 hearing against the underside of the lever26.

In order to depress the extensible rod, the finger arm 27 is pinched topivot the clamping member 26 against the pressure of the compressionspring to a position substantially normal of the extensible rod so thatthe rod may be allowed to slide therein. Upon release of the rod fromengagement with the member 26, the extension rod is ordinarily lightlyrestrained by the friction sleeve 33 within the compression spring.Therefore, it is usually necessary to exert a light pressure upon theextension rod to telescope it within the tubular supporting member.

The foregoing detailed description is given for clearness ofunderstanding only and no unnecessary limitations The outward movementof the 3 should be understood therefrom, for some modifications will beobvious to those skilled in the art.

We claim:

1. A portable stand, comprising a tubular standard supported in anupright position, an extension rod telescoping into the upper end ofsaid standard, said stand ard having a longitudinal slot extendingdownward from its upper end and having a bayonet slot extendinglaterally from said longitudinal slot and then upwardly to form a seat,a cap on the upper end of said standard perforated to receive and guidesaid extension rod and having a lug thereon to coact with the seat ofsaid bayonet slot for securing said cap, a nipping lever fulcrumed onsaid standard on an axis transverse to said extension rod and adapted tohold said extension rod, a helical spring bearing between said cap andsaid nipping lever to normally tilt said nipping lever downward intoholding engagement with said extension rod and to normally urge said capupward to lock said lug in said bayonet slot seat, and an arm on saidlever projecting from said standard for shifting said nipping lever outof its holding engagement with said extension rod.

2. A portable stand comprising: a tubular standard supported in anupright position; an extension rod telescoping into the upper end ofsaid standard, said standard being provided with a longitudinal slotextending downwardly from its upper end and having an upturned portionforming a seat; a cap on the upper end of said standard, said cap beingperforated to receive and guide said extension rod and being providedwith a lug for coacting with said seat to detachably secure the cap tothe tubular standard; a clamping member adapted to hold said extensionrod, said clamping member being 4 fulcrumed on said standard on an axistransverse to said extension rod and being provided with an armprojecting from the standard for moving the clamping member out ofholding engagement with said extension rod; and a coiled spring bearingbetween said cap and said clamping member normally to tilt the clampingmember downward into holding engagement with said extension rod andnormally to urge said cap upward to lock the lug in said seat.

3. A portable stand as specified in claim 2, in which the coiled springembraces the extension rod, and a pad of fibrous material is positionedwithin said coiled spring and about the extension rod, said coiledspring maintaining said pad of fibrous material in close frictionalengagement with said extension rod so that the extension rod isrestrained against downward movement when the clamping member isreleased from holding engagement.

References Cited in the file of this patent UNITED STATES PATENTS179,134 Rand June 27, 1876 1,309,375 Taylor July 8, 1919 1,372,456Roetter Mar. 23, 1921 1,434,322 Wigzell Oct. 31, 1922 1,456,333 NelsonMay 22, 1923 2,051,969 Shastock Aug. 25, 1936 2,337,719 Hueglin Dec. 28,1943 2,442,779 Oriold June 8, 1948 2,483,395 Benson Oct. 4, 19492,588,682 Wyeth Mar. 11, 1952 2,591,686 Des Mais et al. Apr. 8, 1952

